How to design the high Voltage capacitor？

[staric]

How about the capacitors in series for high voltage application? I need some high voltage cap, but these is no device from the model. So I would use the capacitors
in series. But I cannot sure the reliability for the method.

 

[SherpaDoug]

What sort of capacitance and voltage are you talking about? When using caps in series you usually need a resistor divider to make sure they share the voltage evenly. Make the divider current like 10x the worst case cap leakage. If you get over 1kV you really need those resistors to make sure they will self discharge when the input is "off", so they don't kill people. Also beware of "soakage" or dielectric absorption. A discharged cap may recharge itself enough over time to give you a nasty shock. Above 10kV you really need to start thinking about corona discharge and X ray emission. I have never seriously worked with higher voltages than that.

 

[chuckey]

SherpaDoug has it right, just make sure that if you are cascading ,say 450V capacitors, that the bleed resistors are also rated at this voltage or use several in series to get the voltage rating.
Frank